Oh Eye Zero: 16 Analog Inputs for the Raspberry Pi

Description

It isn’t an IO Board, it’s an “Oh Eye” board: sixteen 10-bit analog inputs. It makes it easier to use the Pi as part of a special purpose appliance or musical instrument. The analog inputs are via two MCP3008 chips connected to the Raspberry Pi’s hardware SPI interface. The use of this ADC chip with the Pi is common and well documented. You may ask: “isn’t 16 channels of analog input a little overkill?” To which I would answer: yes it is, except when it isn’t.

There’s also a larger version of the Oh Eye that has a few digital inputs and other interfaces pulled out to headers.

A Mess of Inputs

Once you’ve done a number of projects with a lot of potentiometers or analog sensors you’ll appreciate the handiness of the convenience headers. When you’re using analog inputs you are always running three wires to everything: power, ground, and signal.

Attach up to 16 analog sensors like this accelerometer (left) or 8 digital inputs like this button (right).

The convenience header makes it easy to use three-wire servo cables. With these cables you get a nice solid connection that isn’t going to break at the joint over time, and you can disconnect your panel of pots when you need to. No more stripping dozens of connections (although you can still do that if you like).